An algorithm for automatically generating gas, bone and foreign body visualizations from postmortem computed tomography data.

Post mortem computed tomography (PMCT) can aid in localizing foreign bodies, bone fractures, and gas accumulations. The visualization of these findings play an important role in the communication of radiological findings. In this article, we present an algorithm for automated visualization of gas distributions on PMCT image data of the thorax and abdomen. The algorithm uses a combination of region growing segmentation and layering of different visualization methods to automatically generate overview images that depict radiopaque foreign bodies, bones and gas distributions in one image. The presented method was tested on 955 PMCT scans of the thorax and abdomen. The algorithm managed to generate useful images for all cases, visualizing foreign bodies as well as gas distribution. The most interesting cases are presented in this article. While this type of visualization cannot replace a real radiological analysis of the image data, it can provide a quick overview for briefings and image reports.

Development of Integrated Device of Trace Bloodstains Imaging and Age Analysis.

ABSTRACT: Objective To develop a device of trace bloodstains imaging and age analysis, so as to provide a non-destructive, simple and objective method for age estimation of bloodstains at the crime scene. Methods Based on the principle of digital imaging and color pattern analysis, the mobile terminal of the device was used to collect images of bloodstains of different ages. The time-dependent pattern of 6 parameters （R, G, B, C, Y, M） reflecting the changes of color of images of different ages was obtained by computer image analysis. A multiparameter comprehensive inference equation of bloodstains age was established and embedded into the device software to realize the intelligent inference of the bloodstains age. Then the capability and reliability of the device was verified. Results This integrated device of bloodstains imaging and age analysis could quickly collect bloodstains at the crime scene and automatically analyze and infer the age of bloodstains combined with related intelligence software. In the blind test, the detection accuracy of this device was 95% in both natural light airtight group and dark airtight group, and 80% in the natural light ventilation group. Conclusion The integrated device of trace bloodstains imaging and age analysis can be used in a simple manner, which provides a new objective method for bloodstains age estimation.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses.

ABSTRACT: Postmortem changes on corpses appear immediately after death, and can transform the original structure characteristics of the corpse to different degrees as well as show specific changes on computed tomography （CT） images, sometimes with false positives and false negatives, influencing the identification of injuries or diseases. This paper systematically summarizes the postmortem changes of computed tomography imaging characteristics on corpses, to further expand the application of virtopsy in the practices of forensic pathology identification, and provide reference for the identification of injuries, diseases and changes after normal death.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses / 法医学杂志

Postmortem changes on corpses appear immediately after death, and can transform the original structure characteristics of the corpse to different degrees as well as show specific changes on computed tomography （CT） images, sometimes with false positives and false negatives, influencing the identification of injuries or diseases. This paper systematically summarizes the postmortem changes of computed tomography imaging characteristics on corpses, to further expand the application of virtopsy in the practices of forensic pathology identification, and provide reference for the identification of injuries, diseases and changes after normal death.

[TIME SINCE DEATH ESTIMATION BY USING THE METHOD OF POLYCRYSTALLINE CEREBROSPINAL FLUID FILMS IMAGES MUTUAL POLARIZATION DEGREE LEVELS DISTRIBUTIONS TWO-DIMENSIONAL MAPPING WITH FINE-SCALE SPATIAL FREQUENCY FILTRATION].

Objective - to develop a method of two-dimensional Stokes-polarimetric spatial-frequency mapping of small-scale components of cerebrospinal fluid to improve the accuracy of post-mortem interval estimation. The object of the study was polycrystalline cerebrospinal fluid films taken from 69 corpses (the main study group) and 20 healthy volunteers (comparison group). For each sample, the coordinate distribution of the values of the complex degree of mutual polarization was determined in the optical arrangement of the Stokes polarimeter. The value of the statistical moments of 1 - 4 orders with further statistical processing was calculated. Time dependences of the variation of the value of the most sensitive statistical moments were built to achiev of values stabilization. The interval and the accuracy of the post-mortem interval were estimated by generalizing of the time dependences of the third and fourth order statistical moments of the polarization maps obtained by the two-dimensional mapping of the values distributions of the complex degree of mutual polarization of the small-scale component of polycrystalline networks of cerebrospinal fluid films. An interval of 10 h and the accuracy of post-mortem interval estimation ΔT = ± 12.5 min was established.

Endocranial illuminator: A technique for transilluminating the skull.

A novel tool, the endocranial illuminator (EI), has been devised to facilitate examination of the interior of the intact human cranium. A number of the endocranial characteristics including cranial thickness, sutural complexities, and foramina are easy visible with this device. The EI enhances the accuracy of anatomical examination of the cranial vault in forensic, archaeological, and historical crania in those cases where they must remain intact. The EI is simple and inexpensive to construct and lightweight so it can be used in the laboratory or easily transported in the field.

VirtoScan - a mobile, low-cost photogrammetry setup for fast post-mortem 3D full-body documentations in x-ray computed tomography and autopsy suites.

Injuries such as bite marks or boot prints can leave distinct patterns on the body's surface and can be used for 3D reconstructions. Although various systems for 3D surface imaging have been introduced in the forensic field, most techniques are both cost-intensive and time-consuming. In this article, we present the VirtoScan, a mobile, multi-camera rig based on close-range photogrammetry. The system can be integrated into automated PMCT scanning procedures or used manually together with lifting carts, autopsy tables and examination couch. The VirtoScan is based on a moveable frame that carries 7 digital single-lens reflex cameras. A remote control is attached to each camera and allows the simultaneous triggering of the shutter release of all cameras. Data acquisition in combination with the PMCT scanning procedures took 3:34 min for the 3D surface documentation of one side of the body compared to 20:20 min of acquisition time when using our in-house standard. A surface model comparison between the high resolution output from our in-house standard and a high resolution model from the multi-camera rig showed a mean surface deviation of 0.36 mm for the whole body scan and 0.13 mm for a second comparison of a detailed section of the scan. The use of the multi-camera rig reduces the acquisition time for whole-body surface documentations in medico-legal examinations and provides a low-cost 3D surface scanning alternative for forensic investigations.

Medico-Legal Aspects of Pulmonary Thromboembolism.

Pulmonary ThromboEmolism (PTE) is an important disease for legal medicine. Because of their sudden lethal onset, generally medicolegal autopsies show few clinical information when PTE is the cause of death. During medicolegal autopsies, the autopsy operator must answer to important questions. For example, autopsy operator can need to assess the casual relationship between PTE and recent accident, such as trauma or long air travel. Furthermore, the autopsy operator needs to investigate the pathology of PTE as a cause of sudden cardiovascular death. It is relatively simple to confirm a fatal massive thromboembolus in the initial stage of thoracic investigations, but sometimes it might be difficult to distinguish this from postmortem clot. In such cases histopathological examination can help in the differentiation. Histological examination is also required for observation of chronological changes of the thrombi. Chronological evaluation is an important factor especially to determine whether the death coincides with the date of a specific accident/event or instead there is an earlier onset of PTE. In addition, histological sections sometimes show additional information, such as tumor fragments in cases of malignancy or small fragments of bone marrow in cases of active resuscitation, that can be useful in a medicolegal scenario. Furthermore, new diagnostic tools are arising, which they can be very helpful in the individuation of this frequently underdiagnosed disease. The goal of our work is to investigate these aspects through the review of the recent literature.

[True color accuracy in digital forensic photography]. / Über die Farbdetailtreue in der digitalen forensischen Fotografie.

Forensic photographs not only need to be unaltered and authentic and capture context-relevant images, along with certain minimum requirements for image sharpness and information density, but color accuracy also plays an important role, for instance, in the assessment of injuries or taphonomic stages, or in the identification and evaluation of traces from photos. The perception of color not only varies subjectively from person to person, but as a discrete property of an image, color in digital photos is also to a considerable extent influenced by technical factors such as lighting, acquisition settings, camera, and output medium (print, monitor). For these reasons, consistent color accuracy has so far been limited in digital photography. Because images usually contain a wealth of color information, especially for complex or composite colors or shades of color, and the wavelength-dependent sensitivity to factors such as light and shadow may vary between cameras, the usefulness of issuing general recommendations for camera capture settings is limited. Our results indicate that true image colors can best and most realistically be captured with the SpyderCheckr technical calibration tool for digital cameras tested in this study. Apart from aspects such as the simplicity and quickness of the calibration procedure, a further advantage of the tool is that the results are independent of the camera used and can also be used for the color management of output devices such as monitors and printers. The SpyderCheckr color-code patches allow true colors to be captured more realistically than with a manual white balance tool or an automatic flash. We therefore recommend that the use of a color management tool should be considered for the acquisition of all images that demand high true color accuracy (in particular in the setting of injury documentation).

Smart platform for the time since death determination from vitreous humor cystine.

In this work, we report the smart application of AgNPs based sensors for determination of time since death (TSD) via recognition and quantification of vitreous humor (VH) cystine as well as provide the portability for on spot determination of TSD. The lower detection limit was found to be 7.0ng/ml with prominent selectivity. It was found that there is a linear correlation between the VH cystine concentration and TSD as the concentration of cystine increases up to 96h±3.9h. Further for the first time TSD determination is given a smart approach and it proves to have a great utility up to 24h±2.6h. The linear regression equation between TSD (the dependent variable), RGB intensity of cystine concentration till 24h (the independent variable) was found to be TSD=26.69+-0.05*x. The proposed method gives the smart detection, portability, rapidity, sensitivity, selectivity as well as cost effectiveness for determination of time since death.

Weapon identification using antemortem CT with 3D reconstruction, is it always possible?--A report in a case of facial blunt and sharp injuries using an ashtray.

An interesting case of homicide involving the use of a heavy glass ashtray is described. The victim, a 81-years-old woman, has survived for few days and died in hospital. The external examination of the victim showed extensive blunt and sharp facial injuries and defense injuries on both the hands. The autopsy examination showed numerous tears on the face, as well as multiple fractures of the facial bones. Computer tomography scan, with 3D reconstruction, performed in hospital before death, was used to identify the weapon used for the crime. In recent years new diagnostics tools such as computer tomography has been widely used, especially in cases involving sharp and blunt forces. Computer tomography has proven to be very valuable in analyzing fractures of the cranial teca for forensic purpose, in particular antemortem computer tomography with 3D reconstruction is becoming an important tool in the process of weapon identification, thanks to the possibility to identify and make comparison between the shape of the object used to commit the crime, the injury and the objects found during the investigations. No previous reports on the use of this technique, for the weapon identification process, in cases of isolated facial fractures were described. We report a case in which, despite the correct use of this technique, it was not possible for the forensic pathologist to identify the weapon used to commit the crime. Authors wants to highlight the limits encountered in the use of computer tomography with 3D reconstruction as a tool for weapon identification when facial fractures occurred.

The importance of post-mortem computed tomography (PMCT) in confrontation with conventional forensic autopsy of victims of motorcycle accidents.

Since traffic accidents are an important problem in forensic medicine, there is a constant search for new solutions to help with an investigation process in such cases. In recent years there was a rapid development of post-mortem imaging techniques, especially post-mortem computed tomography (PMCT). In our work we concentrated on a potential advantage of PMCT in cases of motorcycle accident fatalities. The results of forensic autopsy were compared with combined results of the autopsy and PMCT to check in which areas use of these two techniques gives statistically important increase in number of findings. The hypothesis was confirmed in case of pneumothorax and fractures of skull, spine, clavicle, scapula, lower leg bones. As for majority of other bone fractures locations and brain injures there were single cases with pathologies visible only in PMCT, but too few to reach expected level of p-value. In case of injuries of solid organs and soft tissues statistical analysis did not confirmed any advantage of unenhanced PMCT use. On the whole it has been shown that PMCT used as an adjunct to forensic autopsy can cause an increase in information about vitally important regions in case of motorcycle accident fatalities.

Smartphone Image Acquisition During Postmortem Monocular Indirect Ophthalmoscopy.

The medical usefulness of smartphones continues to evolve as third-party applications exploit and expand on the smartphones' interface and capabilities. This technical report describes smartphone still-image capture techniques and video-sequence recording capabilities during postmortem monocular indirect ophthalmoscopy. Using these devices and techniques, practitioners can create photographic documentation of fundal findings, clinically and at autopsy, without the expense of a retinal camera. Smartphone image acquisition of fundal abnormalities can promote ophthalmological telemedicine--especially in regions or countries with limited resources--and facilitate prompt, accurate, and unbiased documentation of retinal hemorrhages in infants and young children.

A fast and reliable method for GHB quantitation in whole blood by GC-MS/MS (TQD) for forensic purposes.

Gamma-hydroxybutyric acid (GHB) is an endogenous compound with a story of clinical use since the 1960s. However, due to its secondary effects, it has become a controlled substance, entering the illicit market. A fully validated, sensitive and reproducible method for the quantification of GHB by methanolic precipitation and GC-MS/MS (TQD) in whole blood is presented. Using 100µL of whole blood, obtained results included a LOD and LLOQ of 0.1mg/L and a recovery of 86% in a working range between 0.1 and 100mg/L. This method is sensitive and specific to detect the presence of GHB in small amounts of whole blood (both ante-mortem or post-mortem), and is, to the authors' knowledge, the first GC-MS-MS TQD method that uses different precursor ions and product ions for the identification of GHB and GHB-D6 (internal standard). Hence, this method may be especially useful for the study of endogenous values in this biological sample.

Characterisation of the weapon used in a patricide by SEM/EDS analysis of a microscopic trace from the object.

This article presents a case of patricide. The murder was characterised by multiple blunt traumas and asphyxia. A mass of contused wounds was localised to the head and neck, and included the complete avulsion of the left eye (by an unknown tool), which was recovered near the cadaver. This case is of interest due to the possibility of identifying microscopic traces of the object that was used for the homicide by examining the skin margins around the ocular injury. The analysis was conducted using scanning electron microscopy combined with energy dispersive X-ray analysis (SEM/EDX). Analysis of the skin margins allowed microscopic inorganic traces to be detected, which were identified as ceramic material. This result focused the attention of the investigation on a small fish-shaped statue that had been previously found by the police when examining the crime scene. The use of SEM/EDX was therefore essential in determining a match between the microscopic traces detected on the perilesional skin and the composition of the statue. This led to the suspicion that the statue was the murder weapon.

Los peritajes médicos en la Valencia bajomedieval: los casos de envenenamiento / Medical expert reports in the Valencia of the late Middle Ages: cases of poisoning

En las últimas décadas del siglo XIII, en pleno proceso de configuración del nuevo Reino de Valencia y de su medicalización, se vislumbró por parte de las autoridades y de los ciudadanos el papel que podían desarrollar los médicos para esclarecer muertes violentas. Fue el problema del posible envenenamiento de un individuo la primera circunstancia que obligó a los jueces a recurrir a los médicos, pues éstos podían con su conocimiento experto contribuir a dilucidar la verdad. Por eso se les pidió incluso el uso de la disección post mortem, si era necesario. En realidad, los médicos fueron conscientes de sus limitaciones en este campo y de que debían actuar con cautela (AU)

During the last decades of the 13th century, in the midst of the shaping and medicalization of the new Kingdom of Valencia, the authorities and citizens envisaged the role that physicians could have in clarifying violent deaths. The first circumstance that compelled judges to resort to physicians was the possible poisoning of an individual, given that they could contribute to elucidating the truth with their expert knowledge. They were even requested to use post-mortem dissection if necessary for this purpose. In reality, physicians were conscious of their limitations in this field and the need for them to act with caution (AU)

[The application of the methods for the measurement of tissue pressure during the comprehensive evaluation of the state of cadaveric tissues for the purpose of forensic medical expertise].

The present paper reports the results of the application of measurements of cadaveric tissue pressure (CTP) in forensic medical thanatology for the determination of the initial position of the corpse and the identification of the visually undetectable bleeding sites on the scalp during examination at the place of its discovery. Moreover, the study of the tissue pressure parameters in the affected tissues may be used to determine the intravitality of the injury and dynamics of its prescription. The parameters of intra-organ tissue pressure suggest its dependence not only on the prescription of the death and manifestations of the postmortem processes but also on the character and extent of the pathological process in the tissues of the organ of interest; these findings can be used for the verification of various diagnostic procedures including those for the objective elucidation of the cause of the death. It is concluded that the investigations along these lines extend the possibilities for the use of quantitative parameters of CTP for the substantiation of expert conclusions based on the results of forensic medical examination.

Feasibility of post mortem cardiac proton density weighted fast field echo imaging in two cases of sudden death.

OBJECTIVE: The aim of this work is to investigate and compare cardiac proton density (PD) weighted fast field echo (FFE) post-mortem magnetic resonance (PMMR) imaging with standard cardiac PMMR imaging (T1-weighted and T2-weighted turbo spin-echo (TSE)), postmortem CT (PMCT) as well as autopsy. MATERIALS AND METHODS: Two human cadavers sequentially underwent cardiac PMCT and PMMR imaging (PD-weighted FFE, T1-weighted and T2-weighted TSE) and autopsy. The cardiac PMMR images were compared to each other as well as to PMCT and autopsy findings. RESULTS: For the first case, cardiac PMMR exhibited a focal region of low signal in PD-weighted FFE and T2-weighted TSE images, surrounded by a signal intense rim in the T2-weighted images. T1-weighted TSE and PMCT did not appear to identify any focal abnormality. Macroscopic inspection identified a blood clot; histology confirmed this to be a thrombus with an adhering myocardial infarction. In the second case, a myocardial rupture with heart tamponade was identified in all PMMR images, located at the anterior wall of the left ventricle; PMCT excluded additional ruptures. In PD-weighted FFE and T2-weighted TSE images, it occurred hypo-intense, while resulting in small clustered hyper-intense spots in T1-weighted TSE. Autopsy confirmed the PMMR and PMCT findings. CONCLUSIONS: Presented initial results have shown PD-weighted FFE to be a valuable imaging sequence in addition to traditional T2-weighted TSE imaging for blood clots and myocardial haemorrhage with clearer contrast between affected and healthy myocardium.

Bone marrow edema induced by a bullet after a self-inflicted accidental firing.

We present a case of a postmortem finding of bone marrow edema in postmortem magnetic resonance imaging (PMMR) indirectly induced by a bullet, which barely missed the bone of a 92-year-old man found kneeling in front of his bed of a tidy apartment. Additionally, a selective postmortem computed tomography angiography (PMCTA) of the left leg was performed, visualizing a laceration of the left femoral vein by the bullet with consecutive contrast media extravasation. A vast pulmonary fat embolism was diagnosed and together with the blood loss found to be the cause of death.

An autopsy case of otogenic intracranial abscess and meningitis with Bezold's abscess: evaluation of inflammatory bone destruction by postmortem cone-beam CT.

The deceased was an unidentified young male found unconscious on a walkway. On autopsy, outer and inner fistulae of the left temporal bone, subcutaneous abscess in the left side of the neck and head, and an intracranial abscess were noted. A portion of the left temporal bone was removed and scanned by cone-beam computed tomography (CT) (normally used for dentistry applications) to evaluate the lesion. The cone-beam CT image revealed roughening of the bone wall and hypolucency of the mastoid air cells, consistent with an inflammatory bone lesion. According to autopsy and imaging findings, the cause of death was diagnosed as intracranial abscess with Bezold's abscess secondary to left mastoiditis as a complication of otitis media. Although determining the histopathology of bone specimens is time-consuming and costly work, we believe that use of cone-beam CT for hard tissue specimens can be useful in forensic practice.